Momentum and Collisions?

Question

Two carts with masses of 4.60 kg and 3.04 kg move toward each other on a frictionless track with speeds of 5.37 m/s and 3.35 m/s respectively. The carts stick together after colliding head-on. Find the final speed.

Answer 1

Use conservation of momentum
4.6*5.37-3.04*3.35=7.64*v
Solve for v
1.9 m/s in the direction that the 4.6 kg cart was moving.
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